Our overall objectives are to study physiologic, chemical and immunologic alterations in cardiac and pulmonary lymph under various experimental conditions, particularly myocardial infarction, and related conditions. Our goals included investigation of the possibility of an alternative method of chemical diagnosis of myocardial infarction to supplement those currently available by the application of immunologic methodology; to explore the pathophysiology of extension of myocardial infarcts using our techniques for the collection and analysis of cardiac lymph, bearing in mind that therapeutic applications are a possibility; to improve our understanding of the canine lymph model by dye studies, lymphangiography, flow studies and chemical and cellular analysis; to investigate the possible role of the pulmonary lymphatics in the clearance of inhaled particles analogous to those which are air pollutants.